Bug 840574 - Add applicationId to tabs; use it to open new urls in the correct tabs. r=margaret

Note that I'm not actually sure where delayLoad and selected are used by
Gecko and thus the side effects of changing them (but I did set the flags
as I'd expect for them to work).

mobile/android/base/Tab.java

@@ -50,6 +50,7 @@ public class Tab {
     private String mTitle;
     private Bitmap mFavicon;
     private String mFaviconUrl;
+    private String mApplicationId;
 
     // The set of all available Favicons for this tab, sorted by attractiveness.
     final TreeSet<RemoteFavicon> mAvailableFavicons = new TreeSet<>();
@@ -194,6 +195,14 @@ public class Tab {
         return mFavicon;
     }
 
+    protected String getApplicationId() {
+        return mApplicationId;
+    }
+
+    protected void setApplicationId(final String applicationId) {
+        mApplicationId = applicationId;
+    }
+
     public BitmapDrawable getThumbnail() {
         return mThumbnail;
     }